FAST92 Loctite or not?
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 962
Likes: 1
From: Lilburn GA
FAST92 Loctite or not?
I'm getting sick or torquing my intake bolts.
I started off with the 89in lbs, and have worked up to 10ft lbs or 120 in lbs.
I do some spirited driving, recheck, and it wont hold the torque.
I've read a Tony Mamo recommendation of 12ft lbs but am afraid I'll break them off in the head. ( Have been there before, don't want to be reverse drilling again ) I do about 3 passes per the order suggested each time, and have had to redo it 4 times now.
I need to put this blasted FAST92 to rest and move on to other mods, knowing I don't have a intake leak.
Should I go for the 12ft lbs?
Should I pull them all out and put some blue loctite on them, then torque them down to ????
Oh, I'm using the stock bolts with the 8mm head and not the ones they sent with the recessed torx heads in them. I did replace the valley bolts with the ones they sent.
Your Expertise will be greatly appreciated, Ken . . .
I started off with the 89in lbs, and have worked up to 10ft lbs or 120 in lbs.
I do some spirited driving, recheck, and it wont hold the torque.
I've read a Tony Mamo recommendation of 12ft lbs but am afraid I'll break them off in the head. ( Have been there before, don't want to be reverse drilling again ) I do about 3 passes per the order suggested each time, and have had to redo it 4 times now.
I need to put this blasted FAST92 to rest and move on to other mods, knowing I don't have a intake leak.
Should I go for the 12ft lbs?
Should I pull them all out and put some blue loctite on them, then torque them down to ????
Oh, I'm using the stock bolts with the 8mm head and not the ones they sent with the recessed torx heads in them. I did replace the valley bolts with the ones they sent.
Your Expertise will be greatly appreciated, Ken . . .
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
I bought a set of ARP 12 point SS bolts as replacement, torqued them to 12ft lbs. with Loctite, and now enjoy a cool look and tight fit. Keep in mind the blue Loctite is only rated to 190 degrees F, but I havn't had an issue with it. I have taken my manifold off since using this proc, and when you do you have to do your best to get as much of the threadlock off the mating surfaces when doing so.
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 962
Likes: 1
From: Lilburn GA
I bought a set of ARP 12 point SS bolts as replacement, torqued them to 12ft lbs. with Loctite, and now enjoy a cool look and tight fit. Keep in mind the blue Loctite is only rated to 190 degrees F, but I havn't had an issue with it. I have taken my manifold off since using this proc, and when you do you have to do your best to get as much of the threadlock off the mating surfaces when doing so.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
I didn't loctite mine and have no leaks. The gaskets settle over time and you will lose torque. Loctite won't correct that and is only good where vibration could potentially work a bolt loose. In my opinion, tighten them evenly and correctly and move on.
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
Bob makes a good point. I remember now I used the FAST gaskets also. They were a bit thicker and I didn't notice as much settling. I'm not saying the stock bolts or the FAST bolts won't cut it. I went with the ARPS because they look good AND they are a bit stronger.
FWIW I had one of the early FAST intakes that were warped. I had Tony Mamo port it for me and he told me when I put it on just 'tighten it down until it's tight'. I did that and it actually straightened out after a while because the next time I took it off it was straight.
BTW, can I ask why you say it's leaking? I never tightend to 89 in. lbs. I always went to 10 lb ft. Maybe my wrench was out?
FWIW I had one of the early FAST intakes that were warped. I had Tony Mamo port it for me and he told me when I put it on just 'tighten it down until it's tight'. I did that and it actually straightened out after a while because the next time I took it off it was straight.
BTW, can I ask why you say it's leaking? I never tightend to 89 in. lbs. I always went to 10 lb ft. Maybe my wrench was out?
Last edited by ArKay99; Jul 2, 2009 at 07:33 PM.
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 962
Likes: 1
From: Lilburn GA
I ripped it off. Its sitting in my garage with Black RTV hardening around the MAP sensor in the back of it.
My plans are to loctite it when I put it back and go to 11 ft pounds.
I took an EFILIve Black Box log while at Road Atlanta, see the pic and blow it up full size. You will notice that my AFR isn't following commanded and that my Long FTRims are maxed out. The EFI guys quickly cried leak. I checked my wonderful FAST bolts and they are at about 6lb torque. That plus the little MAP sensor dangling around on the back
I'm trying to tune my car and absolutely need to know this isn't taking in unwanted air. I've since then been going through the AutoVE tune and have got my AFR very close to the Commanded and the fuel trims are down to normal. This is with me tightening this thing all the time. Fourth time was before I made this post where I torqued it down good, then found after a couple spirited drives, the torque was gone.
Oh, I am using the FAST gaskets. They are tough little rubber rings for sure.
My plans are to loctite it when I put it back and go to 11 ft pounds.
I took an EFILIve Black Box log while at Road Atlanta, see the pic and blow it up full size. You will notice that my AFR isn't following commanded and that my Long FTRims are maxed out. The EFI guys quickly cried leak. I checked my wonderful FAST bolts and they are at about 6lb torque. That plus the little MAP sensor dangling around on the back
I'm trying to tune my car and absolutely need to know this isn't taking in unwanted air. I've since then been going through the AutoVE tune and have got my AFR very close to the Commanded and the fuel trims are down to normal. This is with me tightening this thing all the time. Fourth time was before I made this post where I torqued it down good, then found after a couple spirited drives, the torque was gone.
Oh, I am using the FAST gaskets. They are tough little rubber rings for sure.
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 962
Likes: 1
From: Lilburn GA
Ok, since you brought it up. Here's the crappy thingy I do. Feel free to suggest away.
I have a socket wrench where the socked goes up into the ratchet kindof inversed (Kobalt from Lowes). Fits under the firewall well this way. No way could I get a torque wrench on it. I don't know how anybody does. So As I'm working my way around the other 8, I'll put this little guy on one after using the torque wrench to feel how hard it is to turn with this little inverse wimpy socket. I then take my best guess on the two under the firewall.
I have a socket wrench where the socked goes up into the ratchet kindof inversed (Kobalt from Lowes). Fits under the firewall well this way. No way could I get a torque wrench on it. I don't know how anybody does. So As I'm working my way around the other 8, I'll put this little guy on one after using the torque wrench to feel how hard it is to turn with this little inverse wimpy socket. I then take my best guess on the two under the firewall.
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Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 962
Likes: 1
From: Lilburn GA
Well, if I go to 11lb, blue loctite, and also mark the bolt heads to see if they back out. If the loctite works and they do not back out. I think the gaskets settling at that point will still be within range of 80in pounds. I will do many passes to get it even as possible.
If this doesn't work. Next thing I do will be put LS6 back on and sell the FAST. I've put enough effort into it that if it doesn't work after this, it just isn't engineered or documented well enough. BTW, the docs say 89in pounds, so the instructions already doom every install to utter failure.
If this doesn't work. Next thing I do will be put LS6 back on and sell the FAST. I've put enough effort into it that if it doesn't work after this, it just isn't engineered or documented well enough. BTW, the docs say 89in pounds, so the instructions already doom every install to utter failure.
Race Director
Joined: May 2004
Posts: 16,667
Likes: 1,209
From: Raleigh, NC
St. Jude Donor '15
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Here is my personal opinion for what its worth. Using Loctite won't stop gasket creep, which will occur. The long bolts will develop a stretch at 89 lb-in. Not sure what GM used for material or portion of fastener strength to establish 89 lb-in, but at 11 lb-ft you are increasing the fastener preload by 50%. I wouldn't be surprised if the bolts yield or worse the threads in the heads are damaged, especially if you don't have an accurate torque wrench in the measurement range. I usually install the intake and then go around until all bolts are at 4 lb-in (that is correct, lb-in). Then I go to 10 lb-in and when all bolts hold that value I mark the 12 o'clock position and then rotate each 1/2 turn at a time measuring torque as I go to reach the 89 lb-in. In my discussions with Tony he told me he just snugs them as is good to go so my method is a little more involved but once tight, the bolts never turn. I would be willing to bet they are not at 89 lb-in right now though either.
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 962
Likes: 1
From: Lilburn GA
I started below 89 and have worked my way up 4 times. The last time they were still around 6 or 7 ft lb. Now at this point I'm getting pretty good tune with my AFR very close to command so maybe I would have been ok with that last torque to 10ft lb, even it if backed off to 8ft lb. Maybe I would never have to look at it again.
So guys, I'm very uncertain weather I should go tighter than 10ft lb and put the loctite on or just stay at 10ft lb. At least I've sealed up that MAP real good.
Of course with those last two bolts, you can't just pull them out anytime you want. You have to pull the intake to get them out. So I have to decide loctite or no loctite. I should have called FAST today. I doubt they would be open tomorrow. I have seen many other people with this same problem. I saw Tony say 12ft lb, and many say 10-12 ft lb, and some use loctite.
What to do, what to do?
So guys, I'm very uncertain weather I should go tighter than 10ft lb and put the loctite on or just stay at 10ft lb. At least I've sealed up that MAP real good.
Of course with those last two bolts, you can't just pull them out anytime you want. You have to pull the intake to get them out. So I have to decide loctite or no loctite. I should have called FAST today. I doubt they would be open tomorrow. I have seen many other people with this same problem. I saw Tony say 12ft lb, and many say 10-12 ft lb, and some use loctite.
What to do, what to do?
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 962
Likes: 1
From: Lilburn GA
Pro
Joined: Mar 2004
Posts: 653
Likes: 0
"Watching the needle" indicates you're using a beam-type torque wrench. Toss it in the trash and buy a breakaway torque wrench if you want accurate tightening. You dial in the torque you want, tighten until the head clicks, and you're done.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
That torque wrench is not adequate for these low values. You need a wrench that measure in "lb-in". This may be a good part of your problem, the values are likely off and inconsistent between bolts as well.
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 962
Likes: 1
From: Lilburn GA
I'm still dorking around with my DRM brake ducts. I hate those hoses with the wires in them 
Anyway, I got a little clicker type torque once but just didn't feel it was clicking rigth. I'll go get another one in a bit and put the intake on. I'll compare the two till I get used to the clicker. They work great on my lug nuts, but I don't know about the lighter weight ones, but I'll give it another try.
Thanks for the advice guys, I want to do it right.
Anyway, I got a little clicker type torque once but just didn't feel it was clicking rigth. I'll go get another one in a bit and put the intake on. I'll compare the two till I get used to the clicker. They work great on my lug nuts, but I don't know about the lighter weight ones, but I'll give it another try.Thanks for the advice guys, I want to do it right.
Race Director
Joined: May 2004
Posts: 16,667
Likes: 1,209
From: Raleigh, NC
St. Jude Donor '15
Go get a nice one that is small enough to adjust in inch-lbs. At worst you can use it once and take it back for a refund so it doesn't cost you anything.
